To view all of your upcoming activities on a calendar within the Pipedrive app, simply click the calendar icon from the bottom of the app's home screen, then switch to calendar by tapping the option at the top of the screen. This will take you to your activities list - from there, press the same calendar icon (now at the top of the screen), and that'll take you to your calendar.
To get back to the list from calendar view, simply click the four line icon in the top right.
The calendar will then give you all the activities scheduled for that day in a calendar format, and you can view the schedule of future days simply by selection them from the top.
That way, you can see what time your day starts, finishes, and prevent double-booking activities!